Department of Obstetrics and Gynecology, Hamamatsu University School of Medicine, 1-20-1 Handayama, Higashi-ku, Hamamatsu city, Shizuoka 431-3192, Japan.
Department of Obstetrics and Gynecology, Japan Community Health care Organization (JCHO) Mishima General Hospital, 2276 Yata Aza Fujikubo, Mishima city, Shizuoka 411-0801, Japan.
Int J Med Sci. 2019 Mar 9;16(4):501-506. doi: 10.7150/ijms.31153. eCollection 2019.
To demonstrate the differences in intrauterine fetal deaths and neonatal deaths between small for date (SFD) and Non-SFD neonates by applying a novel classification from both Z scores of placental weight (PW) and fetal/placental weight ratio (F/P) to small for gestational age (SGA) neonates. From 93,034 placentas/infants of mothers who vaginally delivered a singleton infant (Japan Perinatal Registry Network database 2013), SGA (n=7,780) was chosen according to the reference to Japanese neonatal growth chart. They were divided into two subgroups: SFD (body weight and height less than the 10 percentile, n=3,379) and Non-SFD (only body weight less than the 10 percentile, n=4,401). Z scores of PW and F/P based on the standard curves for sex-, parity-, and gestational-age-specific PW and F/P were calculated. The population was classified into 9 groups according to the combination of 'low vs. middle vs. high' i) PW Z score and ii) F/P Z score. In both i) and ii), ± 1.28 standard deviations in the Z scores were used for classifying low vs. middle vs. high, with 3×3 making 9 groups. From top-left to bottom-right, we labeled the groups as Group A to Group I. SFD and Non-SFD neonates distributed in the same 6 groups (A, D, E, G, H, I). In group E, which was considered to be balanced placental and infant growth, the incidence of intrauterine fetal death was significantly higher in Non-SFD neonates than in SFD neonates. In group D, which was considered to be small placenta and balanced infant growth, the incidence of neonatal death was significantly higher in SFD neonates than in Non-SFD neonates. Assessment of SGA neonates by dividing them into SFD and Non-SFD neonates and application of a 9-group classification by PW and F/P Z scores were informative to understand the pathophysiological involvement of an imbalance between placental and fetal sizes.
为了通过应用一种新的分类方法，即胎盘重量 (PW) 和胎儿/胎盘重量比 (F/P) 的 Z 分数，来显示胎龄小的胎儿死亡和新生儿死亡与非胎龄小的胎儿死亡和新生儿死亡之间的差异，我们选择了 93034 例阴道分娩的单胎产妇的胎盘/婴儿数据（日本围产期登记网络数据库 2013 年）。根据日本新生儿生长图表的参考标准，选择了 SGA（n=7780）。他们被分为两个亚组：SFD（体重和身高小于第 10 百分位，n=3379）和 Non-SFD（仅体重小于第 10 百分位，n=4401）。基于性别、产次和胎龄特异性 PW 和 F/P 的标准曲线计算了 PW 和 F/P 的 Z 分数。根据“低、中、高”i）PW Z 分数和 ii）F/P Z 分数的组合，将人群分为 9 组。在 i）和 ii）中，PW 和 F/P 的 Z 分数的正负 1.28 个标准差用于将低、中、高分类，3×3 共分为 9 组。从左上角到右下角，我们将这些组标记为 A 到 I 组。SFD 和 Non-SFD 新生儿分布在相同的 6 个组（A、D、E、G、H 和 I）中。在被认为是胎盘和婴儿生长平衡的 E 组中，非 SFD 新生儿的宫内胎儿死亡发生率明显高于 SFD 新生儿。在被认为是胎盘小且婴儿生长平衡的 D 组中，SFD 新生儿的新生儿死亡发生率明显高于 Non-SFD 新生儿。将 SGA 新生儿分为 SFD 和 Non-SFD 新生儿，并应用 PW 和 F/P Z 分数的 9 分组分类，有助于了解胎盘和胎儿大小失衡的病理生理参与。
